When I was in graduate school (in Minnesota), I had a bunch of other grad students, several of them foreign, over at my apartment for spaghetti. Someone sneezed, I automatically said "Gesundheit," and was rewarded by one of the funniest double-takes I ever saw from the German grad student...

bearing - my daughter tells a similar story. While spending her junior year in Frieburg (from the UofM), through a conversation with housemates, they were amazed that 'Gesundheit' was the reply she had grown up with. Milwaukee-German, this one.